SCHENECTADY -- Emergency workers on Thursday descended on the area around City Hall to investigate a suspicious propane tank.

Police were called to the area after a motorist spotted the tank behind the post office on Clinton Street and flagged down a city worker.

State Police bomb experts examined the rusted tank and removed it around 10:15 a.m. City Hall remained open but the post office and the main county library branch across the street were evacuated, police said.

The incident came roughly 24 hours before President Obama was scheduled to visit the city's General Electric plant.

Patrolman Michael Crounse said there was nothing to indicate that the placement of the tank had anything to do with the President's visit.

"I can't speculate on that," Crounse said. "We followed protocol. The President coming or not, there was a suspicious object. That is a serious situation."